Among hydraulic pressure generation apparatus that generate a brake hydraulic pressure according to a stroke length (action length) of a brake pedal is one that is equipped with a master cylinder for generating a brake hydraulic pressure by a piston linked to the brake pedal, a stroke simulator for giving a simulated manipulation reaction force to the brake pedal by a piston that is urged, and a slave cylinder for generating a brake hydraulic pressure by a piston having a motor as a drive source.
In an example of the above-type of hydraulic pressure generation apparatus, the master cylinder, the stroke simulator, and the slave cylinder are provided in a single base body (refer to JP-2014-525875-A, for example).
In this conventional hydraulic pressure generation apparatus, cylinder holes of the master cylinder and the stroke simulator have respective openings in a rear surface of the base body and a cylinder hole of the slave cylinder has an opening in a right side surface of the base body.
Thus, the cylinder holes are formed by machining from different directions and various components are set in the cylinder holes from different directions. This means a problem that manufacture of this conventional hydraulic pressure generation apparatus requires complicated steps of work.
Furthermore, in this conventional hydraulic pressure generation apparatus, since the two cylinder holes of the master cylinder and the stroke simulator have respective openings in a rear surface of the base body and the cylinder hole of the slave cylinder has an opening in a right side surface of the base body, the brake pedal is disposed on the side of the rear surface of the base body and the motor is attached to the right side surface of the base body. And a right side portion of the base body is provided with a drive power transmission unit for inputting, to the slave cylinder, motive power that originates from rotational drive power of the output shaft of the motor. Thus, the one side portion of the base body is made large and the motor projects to a large extent from the one side surface of the base body. This means a problem that it is difficult to secure a space for installation of the hydraulic pressure generation apparatus in a vehicle.